1. Field of the Invention
The present invention relates generally to dome security cameras and, more particularly, to a dome security camera, in which a knob is provided on the outside of the lower portion of a casing having a sensor and LEDs therein to prevent a dead zone from being created, thus allowing a larger number of LEDS to be installed in the casing, and the knob is disposed on the outside of the casing, thus allowing the position of the sensor to be freely changed without changing the position of the knob, even though the casing is rotated.
2. Description of the Related Art
Generally, security cameras are installed in or outside areas that may need surveillance such as offices, houses, hospitals, banks, and public establishments and are used to control people's entry or prevent crimes. In recent years, the installation of the security cameras is increasing in underground parking lots where the number of crimes is on the rise, roads for illegal parking control, or residential areas where various accidents frequently take place.
The security cameras are classified into standard cameras, zoom cameras, dome cameras, and speed dome cameras. Particularly for the dome cameras, when they are installed in consideration of interior design they are problematic in that a camera is fixed, so that only one point of the associated space is photographed, and thereby the range of the photographed area is limited.
In order to solve the problem, a dome security camera which is constructed so that a lens assembly rotates leftwards/rightwards or upwards/downwards has been proposed.
The dome security camera is constructed to rotate at 360 degrees leftwards/rightwards (hereinafter referred to as ‘pan’), and to rotate at 90 degrees upwards/downwards (hereinafter referred to as ‘tilt’), so that it is able to photograph all points of the associated space.
As such, recently, the photographing direction of the security camera may be adjusted, and in addition, it is possible to photograph even at night or underground where there is no light (visible rays), owing to an infrared (IR) LED lamp.
FIG. 1 is a side view illustrating a conventional dome security camera, and FIGS. 2A and 2B are side views illustrating the operational example of the conventional dome security camera.
As shown in FIGS. 1, 2A and 2B, the conventional dome security camera A′ includes a housing 2′, a hemispherical cover 4′, a camera module, and a bracket 8′. A circuit part (not shown) is installed in the housing 2′. The hemispherical cover 4′ is coupled to the housing 2′. The camera module includes a casing 7′ which has a lens 6′ mounted to the central portion thereof, and has a plurality of IR LEDs 72′ (hereinafter referred to as ‘LED’) around the lens 6′. The bracket 8′ is provided in the housing 2′ so that the casing 7′ is rotatably coupled thereto.
Further, the lens 6′ is coupled to a barrel. The barrel is constructed so that the lens 6′ is moved up and down by rotating a knob 64′ provided on a side of the barrel, thus adjusting a focus. The knob 64′ passes through an actuating hole 74′ formed in the casing 7′ in such a way as to be exposed to the outside.
That is, in order to enable the knob 64′ to be easily manipulated by hand, the knob 64′ is manipulated to be rotated in the actuating hole 74′ of a predetermined length which is formed in the side surface of the casing 7′.
Further, a sensor 9′ for detecting the movement of a subject is embedded in a portion which is opposite the knob 64′.
The use example of the conventional dome security camera A′ will be described. After the cover 4′ is separated from the housing 2′, the knob 64′ is rotated leftwards or rightwards to adjust the focus of the lens 6′. Further, the casing 7′ is rotated to determine the proper irradiation angle of the sensor 9′, and then the cover 4′ is coupled to the housing 2′ again.
Meanwhile, as shown in FIG. 2A, when the casing 7′ and the lens 6′ are maximally moved up to photograph a more distant subject, the sensor 9′ is covered by the upper end 42′ of the cover 4′, thus negatively impacting the functionality.
That is, the cover 4′ is made of a transparent material, but the upper end 42′ is made of an opaque material, thus causing an error in sensing.
Thus, in order to solve the problems, as shown in FIG. 2B, the casing 7′ is rotated so that the position of the sensor 9′ is changed to a lower position at which the knob 64′ is located, and the position of the knob 64′ is changed to an upper position at which the sensor 9′ is located. In this case, the knob 64′ is shifted to the upper position, so that its height is increased. Thereby, it is difficult to manipulate the camera A′ by hand, if the camera A′ is mounted to a ceiling.
Further, the conventional security camera is problematic in that the actuating hole 74′ into which the knob 64′ is fitted occupies a part of the casing 7′, so that a space having no LED 72′, namely, a dead zone is created, and thus infrared irradiating performance is deteriorated.